https://doi.org/10.1007/s100510170112
Charge stripes in the extended Hubbard model with nearest-neighbor Coulomb interaction
Dipartimento di Fisica "E.R. Caianiello" , University of Salerno and
Unità INFM of Salerno, Baronissi (Sa), Italy
Corresponding author: a citro@sa.infn.it
Received:
20
December
2000
Revised:
27
April
2001
Published online: 15 August 2001
Using a strong coupling approach, based on a Cumulant Expansion, we investigate the
stripe orders driven by nearest-neighbor Coulomb (NNC) interaction in the
Hubbard model. When we consider only local Coulomb repulsion, critical charge fluctuations
drive the system towards a phase separation (PS). Such density instability
evolves into an incommensurate
charge density wave (ICDW) when nonlocal Coulomb interactions are taken into account,
similarly to the case when
long-range Coulomb forces are considered. In particular, we find a stripe phase
with a crossover from diagonal to vertical stripes in the doping region
, similarly
to neutron scattering experiments on 
. Analogous strong dependence in the stripe direction is observed at varying the NNC interaction.
PACS: 74.20.-z – Theories and models of superconducting state / 71.45.Lr – Charge-density-wave systems / 71.10.Hf – Non-Fermi-liquid ground states, electron phase diagrams and phase transitions in model systems
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2001
